I also see a quote re GM Alterman DVD re: ...Bg4 6.h3 Bh5!? positional pawn sac which looks deep at first glance - engines may not evaluate this correctly. Opinions?

Haven't looked into this line very much but John Cox advocates it in Dangerous Weapons: Ruy Lopez and concludes: "It seems to me that Black's idea is under the greatest pressure here [after 7.g4 Bg6 8.Nxe5 Qh4 9.Qf3 f6 10.Nxg6 hxg6 11.Kg2 g5 12.d3 without White later playing Nc3], but White has by no means yet shown a clear path to an advantage."